Synonyms of whiner
grouch (informal)A grouch is someone who is always complaining in a bad-tempered way.
• He's an old grouch but she puts up with him.
moanercomplainergrumblerwhinergrousermalcontentcurmudgeoncrosspatch (informal)crab (informal)faultfinder
malcontentYou can describe people as malcontents when you disapprove of the fact that they are dissatisfied with a situation and want it to change.
• Five years ago, a band of malcontents seized power.
Thesaurus for whiner from the Collins English Thesaurus